This invention is related to stream-powered water filters of the rotatable type wherein water is withdrawn from the interior of a rotatable member. More specifically, the invention is related to a water filter used for removing irrigation water from a stream, river, or other running body of water wherein the filter is powered by the water current in the running body of water. Several types of rotary screens and water filters are known in the prior art for filtering debris where water is removed from a river or a standing body of water. In these devices the strainer is in the form of a perforate drum which must be rotated by an external power source and sprayed from the inside with a stream of water for cleaning debris from the strainer. Debris removers are known in the art for removing debris from water as it moves through an irrigation channel. These devices are water-powered and remove debris or trash from the water, however, they have no provisions for removing filtered water from within the strainer and they must be constructed in a ground-mounted water channel. In areas where river water or stream water is used for irrigation purposes the water is generally pumped directly from the stream or river into the irrigating channel or sprinkler system in a field. In this use the inlet of the conduit from the stream to the pump must be provided with a filter in order to prevent debris, trash, and foreign material from entering the conduit and thus entering the pump because such material could damage the pump. In the prior art it is common to provide a screen around the inlet of such a conduit, however, in heavily debris laden streams or rivers the screen quickly plugs with debris and foreign material thereby reducing or substantially stopping water flow into the pump. When this condition occurs, the pump must be stopped and the debris removed from the stationary screen by hand before irrigation can continue.